Door closing unit



Sept 27, 1960 J. HALL 2,953,811

DOOR CLOSING UNIT Filed NOV. 30, 1956 INVENTOR.

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nited States Patent ffice The invention comprises a door closing unit'and more particularly a door check of the reciprocating air type.l

Heretofore, door closing devices of the reciprocating f and have not provided eiiicient and trouble-free operation over an extended period of time. Such devices have been difficult to regulate and have not been readily adapted for various installations. n l l It is therefore a principal object of the invention to provide a new and improved door closing unit which is simple in construction and eicient in operation.

Another object of the invention is to provide a new and improved door closing unit providing trouble-free operation over an extended period of time. v Another object of the invention is to provide a new and improved door closing unit of the airl type, which is light in weight and readily adapted for various installations. Y y

Another object of the invention is to provide a new and improved door closing Yunit which may readily be regulated to control its door closing action;

Another object of the invention is to provide a new and improved door 'closing unit which can be eiciently manufactured and produced at a low cost. o ,y The vabove objects as well as other objects ofthe invention will become more apparent as the following detailed description of the invention is `read in conjunction with the drawing, in which:

I air type have been complex and lcostly to manufacture Y Patented Sept. 27, 1960 A piston rod 28 of substantially cylindrical coniguration-has an outer attaching end 30, an inner piston actuating portion 32, and an intermediate main portion 34.V TheA piston rod 28 passes into the chamber `14 of the body 12 through an opening 36 in the end portion 17 of the body 12. This allows the main portion 34 of the piston rod to be slidably received into the chamber 14 of the body 12, and withdrawn therefrom. The piston actuating portion32 of the rod 28 is substantially cylindrical inform and extends between an end retaining washer 38 and a pair of extending stop portions 40. A pair of opposite attened areas 42 are formed in the cylindrical outer surface of the portion 32 and extend from a location v44 intermediate the retaining washer 38 and the stops 40, in the axial direction to the end l46 of the rod 28; The ilattened areas 42 form openings or clearances 48 through the retaining washer 38 (see Figure 6).

yIn assembling the piston rod 28 and piston 16, the piston actuating portionA 32 a pressure plate or disc 50 which is positioned in abutmentpwith the stops 40. An air sealing ring 51 which may be made of a resilient plastic material is next snugly received about the portion 32 adjacent to the pressure plate 50. The sealing ring 51 is followed by the piston l16 which receives the end portion 32 through its central Figure l is an elevational view -of the doorfclo-sing unit with an end portion broken away, f :Figure `2 is an enlarged sectional view taken on the line 2-2 lof Figure 1 illustrating the piston rod being withdrawn,

-Figure 3 is a sectional view similar to Figure 2 showing the piston Vrod being received into-the unit, ,Figure 4 is a plan view of the piston rod ith a portion broken away, l

Figure 5 is a side elevational vview .of thepiston engagl l ingendportion of the piston rod shownin Figure..4, A Figure 6'is aleft end view of Figure 5,

Figure 7 is a side elevational view of device, and i f Figurev 8 is a left end elevational view of Figure 7.. Like referencenurnerals designate like parts through'- out the several views. f v 5 v Referring to the figures of the drawing, a door closing or check device 10 embodying theV invention, includes an elongated hollow cylindricalbody 12 forming within die pistoniof; the

opening 26. The piston 16 forms a close but movable fit onv the rod 28. The piston 16 is locked on the rod 28 byk the end retaining washer 38 which is next secured at the end 46 of the rod `28.

The piston and rod assembly is receivedv into the chamber 14V before the end portion 17 of the device 1 1.)- is secured with the body 12. A spring engaging disc 5,2. with a central opening is also received over theend 30 of the rod 28- and is positoined in abutting relationship withthe stops 40. A coiled spring 54 is next received about the intermediate portion 34 of therrod 28 kwith its end l56 engaging the disc member 52. When the end portion 17 is secured in position with the body 12, the other extremity 58 of the spring member 54 engages same (see Figure l). The force of the spring 54 urgesrthe rod 28A into the chamber 14 of the body 12, and in the direction towards the end portion 15,01? the body 1.2. It is noted that the movement of the piston 16 with the rod 28 towards the end portion 15 of the body 12 enlarges the volume of the second section 20, while lreducing the volumeof the first sectoin 18 of the chamber '14 withinthe body 12. Conversely, the movement offthe piston 16-towardthe end portionv 17 Vof the body i112'byI the withdrawal ofthe rod 28 from the chamber 14 enlarges the volume of the rst section 18 andreduces thev volume ofthe second section 20 of the chamber 14. v u.

The piston \16 is movable in the axial direction along the piston actuating portion 32 of the rod 28 between its first lterminal position assumed by its contact with `the retaining washer 38 at one extremity, and its second terminal position assumed when it abuts the vsealing'ringj it a cylindrical chamber 14'enclosed by end portions`15 and 17. v A cylindrical piston y16 .is movably received withinl the body 12-,variably partitioningits `chamber 14, into iirst and secondfsectionsrl and 20. `The piston 1.6 hasan ,y annularperipheral groove 22 -receiving withinit a Sealing ring or'washer 24 which movably contacts the'inside :wall

' of thecharnber 14 forsealing itssections 18 4and 20`. The

piston 16 has a central axial openingV 26 extendingfbetween the sections 18 and 2010i the, chamberf14jofthe t, exerted upon the piston rod 28, v'causing it to"bewith' body 12.V

51 and pressure plate 50 at the other extremity. vIt is noted that-the rst terminal position of the rod-28 with the piston'16 is assumed when the rod 28 is being with; drawn from, the chamber 14 of they body 12, whereastlie second terminal position is assumed .when the` rod- 28is being received into the body 12. 'a Q'.

In the operation ofthe door closing orV check device 10, the bracket 60 ofthe end portion 15 andl thevout'er; attaching portion 30 of the rod 28 are vappropriately secured between a supporting structure and-a doolrforother device which is to be controlled. The coiled spring 52 acts to normally maintain .the door in a closed positoin by urging the'piston into the chamber 14 of the body' 12; When' a for s of 'the rod 28 first receives drawn from the body 12 as when the door is being opened the device acts as follows.

The motion of the rod 28 being withdrawn from the chamber 14 of the body 12 causes the rod 28 to assume its first terminal position with respect to the piston 16, whereby the piston 16 contacts the retaining washer 38. The further action of the rod 28 causes the piston 16 to move in the direction of the rod 28. This movement enlarges the volume of the section f18 of the chamber 14, and reduces the volume of the section 20 while compressing the spring 54.

The rod 28 in its first terminal position forms a clearance between the attened portions 42 of the rod 28 and the central opening 26 of the piston 16 providing a passage allowing the ow of fluid from the second section 20 to the first section 18 of the chamber 14. This allows the outward movement of the rod 28 from the body 12 to take place with a minimum amount of resistance by the iiuid within the chamber 14.

During the door closing operation, the coil spring 54 causes the piston rod 28 to be received into the chamber 14 of the body 12. The rod 28 moves with respect to the piston 16 until it assumes its second terminal position, with the piston against the sealing ring 51 and pressure plate 50. In this position, the ends 44 of the flat region 42 are enclosed within the opening 26 of the piston, and the cylindrical portion 33 of the piston actuating portion of the rod 28 is closely received into the opening 26 of the piston 16 effectively restricting the passage of fluid through the opening 26. The ring member S1 which is positioned about the mouth of the opening 26 at this time also serves to seal the opening 26 under the compressive force exerted between the pressure plate 50 and the piston 16. The end of the piston 16 facing the section 20 of the chamber 14 may also be hollowed out as at 62 to provide a clearance for the pressure plate 50, so that the sealing ring 51 may be more effectively compressed to assure good sealing action.

The continued motion of the rod 28 after it assumes its second terminal position with respect to the piston 16 actuates the piston in the direction enlarging the volume of the section 20 and reducing the volume of the section 18 of the chamber 14 of the body 12. This motion is accompanied by the flow of air from the section 18 of the chamber 14 out of the body 12 through the threaded opening 64 and the connecting opening 66 in its end portion 15. The ow of uid through the openings 64 and 66 is regulated by a screw 68 which controllably restricts and provides a variable orifice within the openings. A flow of air takes place from outside of the body 12 into the section 20 of the chamber 14 through the opening 36 in the end portion 17 of the body 12, or through an external vent 58 which may be provided.

By regulating a rate at which air in the chamber section 18 may escape through the passages 64 and 66 by use of the screw 68, the speed with which the rod 28 moves into the body 12 may be controlled. In practice, the screw 68 is adjusted to regulate the speed with which a door of any weight is to be closed.

In general, it will be noted that when the rod 28 is being withdrawn, the piston 16 automatically assumes its rst terminal position with respect to the rod 28 forming an intercommunicating passage between the sections of the chamber 14 which reduces the uid resistance to its motion. The outward motion of the rod 28, however, is opposed by the spring 54 which is compressed by this action.

When the force moving the rod 28 in the outwardly direction is removed, the coiled spring 54 acts to urge the rod 28 into the body 12. Since, however, the tiuid in the section 18 of the chamber 14 can only escape through the restricted passages 64 and 66, the setting of the screw 68 determines the resistance otfered by the duid to` the piston 16 when the rod 28 is being received illlQ the body 12. By regulating the resistance to motion of the rod 28 under the action of the spring 54, the rate at which the rod 28 moves into the body 12 may be controlled.

Since the device 18 is normally attached to perform the closing operation when the rod 28 is being received into the body 12, the speed of the closing motion of the door may thus be regulated by adjusting the screw 68. Since a door or similarstructure is required to close more slowly than it opens, the device 1) by its action just described allows the door to be easily and more quickly opened by offering reduced resistance (when its rod 28 is being withdrawn) during such opening operation.

It will be obvious to those skilled in the art that the invention may find wide application with appropriate modification to meet the individual design circumstances, but without substantial departure from the essence of the invention.

What is claimed is:

1. A door closing unit comprising an elongated cylindrical body with rst and second end portions and having a chamber containing a uid and a controlled opening in the first end portion extending from the chamber to outside of the chamber, a piston movable within said body for variably partitioning said chamber into first and second sections respectively proximate the first and second end portions of said body, said piston having a central opening, a piston rod having an end movably received into said chamber through an opening in the second end portion of said body for actuating said piston, the rst section of said chamber being enlarged upon actuation of said piston by said rod being withdrawn from said body while the second section of said chamber is enlarged upon actuation of said piston by said rod being received into said body, said rod having a reduced portion adjustably slidably received within said central opening of said piston supporting said piston for relative movement, peripheral portions of said reduced rod portion detning with said central opening a uid passage between said piston and rod interconnecting the first and second sections of said chamber when said piston is actuated to enlarge the rst section of said chamber by movement towards the second end portion of said body, said piston rod having an enlarged portion which is received into said piston sealing said uid passage through said piston when said piston is actuated to enlarge the second section of said chamber by movement towards the first end portion of said body, the movement of said piston towards the second end portion of said body enlarging the first section of said chamber causing the transfer of fluid by means of said passage through said piston from the second section to the first section of said chamber, the movement of said piston towards the first end portion of said body enlarging the second section of said chamber being regulated by the metered flow of uid from the first section of said chamber through said controlled opening in the first end portion of said body out of said chamber and causing the ow of fluid from outside of said body into the second section of said chamber through an opening in the second end portion of said body, and a coiled spring within the second section of the chamber of said body positioned about said rod and attached for exerting a force upon said rod for urging it in the direction into the chamber of said body and towards the first end portion of said body for actuating said piston in the direction enlarging the second section of said chamber.

2. A door closing unit comprising a body having a chamber containing a fluid, a piston movable within said body for variably partitioning said chamber into first and second sections and having a circular cylindrical opening therethrough, a piston rod movably received into said chamber for actuating said piston, said rod having a cylindrical end portion received through the opening of said piston and being axially movable with respect to said piston between first and second terminal positions, the cylindrical end portion of said rod having a longitudinal attened area providing a clearance between it and the piston forming a fluid passage through the opening of said piston between the sections of said chamber when said rod is in its iirst terminal position, said flattened area being limited in extent so that said cylindrical end portion closes the opening of said piston and said uid passage is restricted when said rod is in its second terminal position, a ring element mounted o-n said rod adjacent one end of said piston within the second section of said chamber, said ring element being compressed by said piston when said rod is in its second terminal position sealing the opening of said piston, and a retaining washer secured upon the end of said rod, said piston respectively abutting said washer and said ring element when in its rst and second terminal positions.

3. The door closing unit of claim 2 in which said piston frictionally engages said body and said rod assumes its first terminal position with respect to said piston due to the frictional force on said piston when said rod is being withdrawn from said body and assumes its second terminal position with respect to said piston due to the frictional force on said piston when said rod is being received into Isaid body.

4. The door closing unit of claim 3 in which said body has a metering orice extending from the rst sec- 'tion of its chamber to outside of said chamber and the receipt of said rod into said body seals the passage through said piston preventing transfer of uid between the sections of said chamber and causing the metered ow of fluid from said first section of said chamber out of said body and a controlled orifice causing the How of fluid into the second section of said chamber from outside of said chamber.

5. The door closing unit of claim 4 including a spring means within the chamber of said body urging said rod into said body and causing said rod to assume its second terminal position sealing the passage through said piston.

6. The door closing unit of claim 5 in which said body has an elongated cylindrical form, said passage accommodating a larger quantity of Huid llow than said metering orifice, whereby movement of said rod into said body is resisted by a greater force than movement of said rod outwardly thereof.

7. A door closing unit comprising a body having a chamber containing `a fluid and a metering orifice extending from the chamber to outside of the chamber, a piston movable within said body for variably partitioning said chamber into rst and second sections, said piston having a central opening, a piston rod movably received into said chamber for actuating said piston, the rst section of said chamber being enlarged upon actuation of said piston by said rod being withdrawn from said body while the second section of said chamber is enlarged upon actuation of said piston by said rod being received into said body, said rod having a reduced portion adjustably slidably received within said central opening of said piston supporting said piston for relative movement, peripheral portions of said reduced rod portion defining with said central opening a passage through relatively movable parts of said piston and rod interconnecting the rst and second sections of said chamber in one position of said piston upon said rod in response to movement of said piston in one direction relative to said rod to enlarge the rst section of said chamber, said piston rod having an enlarged portion which is received into said piston to seal said passage in another position of said piston upon said rod in response to movement of said piston in another direction along said rod to enlarge the second section of said chamber, the action of said piston enlarging the rst section of Said chamber causing transfer of uid by means of said passage through said piston from the second section to the -rst section of said chamber, the action of said piston enlarging the second section of said chamber causing the metered flow of uid from the rst section of said chamber out of said body through said metering orice and causing the ow of iluid to the second section of said chamber from outside of said body through an opening therein in communication with said second action, and spring means within the chamber of said body acting upon said rod for urging said piston in the direction enlarging the second section of said chamber.

References Cited in the le of this patent UNITED STATES PATENTS 491,794 Barker Feb. 14, 1893 1,147,909 Williams n July 27, 1915 1,799,872 Seipel 1 Apr. 7, 1931 2,091,904 Baumann Aug. 31, 1937 2,153,833 Hartshorn Apr. 1l, 1939 

